In the Western civilization, a third of the population suffers from cancer with a mortality rate of no less than 75%. Malignant tumors are nowadays treated cytostatically.
The main problem with the chemotherapy of those diseases is that the cancer cells respond to the applied cytostatic drug only to a certain percentage. Moreover, a complete remission often cannot even be expected if the tumor does respond to the treatment.
A current trend toward an efficiency increase of the chemotherapy consists in the polychemotherapy, i.e. the use of several cytostatic drugs. More and more frequently, various cytostatic drugs with different application points are combined in order to improve the cancer therapy. Thereby, better efficacy is achieved on the one hand and on the other hand the problem of a progressively developing resistance is countered.
A further possibility consists in selectively protecting the healthy cells from the cytostatic drug by a simultaneous administration of cytoprotectors, whereby a higher dose can be administered, at the same time involving fewer side effects (e.g. taxanes).
Despite those measures, the side-effect rate of chemotherapy is still very high. Precisely for this reason it is of utmost importance to develop drug substances which exhibit good efficacy as well as good tolerance, i.e. which possess a therapeutic window that is as broad as possible.